摘要
Discrete asine transform (DCT) is the key technique in JPEG and MPW, chch dds with tw bforkby block. HoWever, this methed is no sultabe for the blocks conaining many edges for high quality image reconstruc-tion in Particular. An adaptive hybrid DPCM/DCT edng mehed is proposed to solve this problem. For each block,the ds dethetor botches to DPCM or gy ceder autoInaticthe depewhng upon quality requrement. The edge blocksare coded by DPCM coder that adaptively Selects a predictor from the given set, which results in minimum predictionerror, and the hadues obained are ced with fuce ed. For non-edg bforks, us, mlength nd vallabe lengthcoding(VLC) are applied. Experimental results showed the Proposed algorithm ouperforms baseline JPEG and JPEGlossless mode both on compression ratio and decoding run-time at the hit rates from 1 to 4 approximately.
Discrete asine transform (DCT) is the key technique in JPEG and MPW, chch dds with tw bforkby block. HoWever, this methed is no sultabe for the blocks conaining many edges for high quality image reconstruc-tion in Particular. An adaptive hybrid DPCM/DCT edng mehed is proposed to solve this problem. For each block,the ds dethetor botches to DPCM or gy ceder autoInaticthe depewhng upon quality requrement. The edge blocksare coded by DPCM coder that adaptively Selects a predictor from the given set, which results in minimum predictionerror, and the hadues obained are ced with fuce ed. For non-edg bforks, us, mlength nd vallabe lengthcoding(VLC) are applied. Experimental results showed the Proposed algorithm ouperforms baseline JPEG and JPEGlossless mode both on compression ratio and decoding run-time at the hit rates from 1 to 4 approximately.
